时间区间拆分算法

需求描述：

时间范围：2022-04-10 09:00:00 ~ 2022-04-12 18:00:00
具体描述：需要将上边的一个时间范围拆分成若干个时间范围（单位：天）。
实现效果：

(day=2022-04-10, startTime=2022-04-10 09:00:00, endTime=2022-04-10 23:59:59)
(day=2022-04-11, startTime=2022-04-11 00:00:00, endTime=2022-04-11 23:59:59)
(day=2022-04-12, startTime=2022-04-12 00:00:00, endTime=2022-04-12 18:00:00)

项目依赖：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.6.6</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>demo</artifactId>
    <version>0.0.1</version>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>
</project>

代码实现：

@SpringBootTest
public class DemoApplicationTests {
    public static final DateTimeFormatter YYYY_MM_DD = DateTimeFormatter.ofPattern("yyyy-MM-dd");
    public static final DateTimeFormatter YYYY_MM_DD_HH_MM_SS = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");
    public static final String HEAD_DATE_TIME_SUFFIX = " 00:00:00";
    public static final String LAST_DATE_TIME_SUFFIX = " 23:59:59";

    @Builder
    @Data
    static class dayInfo {
        private String day;
        private String startTime;
        private String endTime;
    }

    @Test
    public void testGetDayInfoList() {
        String startTime = "2022-04-10 09:00:00";
        String endTime = "2022-04-12 18:00:00";
        List<dayInfo> dayInfoList = getDayInfoList(startTime, endTime);
        for (dayInfo dayInfo : dayInfoList) {
            System.out.println(dayInfo);
        }
    }

    /**
     * 获取两个时间之间所有的时间（前闭后闭）
     *
     * @param startTime
     * @param endTime
     */
    public List<dayInfo> getDayInfoList(String startTime, String endTime) {
        //解析日期
        String sd = startTime.substring(0, 10);
        String ed = endTime.substring(0, 10);
        //初始时间
        List<dayInfo> dayInfoList = new ArrayList<>();
        List<String> dayList = getDayList(sd, ed);
        for (String day : dayList) {
            dayInfoList.add(dayInfo.builder()
                    .day(day)
                    .startTime(day.concat(HEAD_DATE_TIME_SUFFIX))
                    .endTime(day.concat(LAST_DATE_TIME_SUFFIX))
                    .build());
        }
        //判空处理
        if (dayInfoList == null || dayInfoList.isEmpty()) {
            return dayInfoList;
        }
        //获取头天
        dayInfo head = dayInfoList.get(0);
        String headDay = head.getDay();
        String headStartTimeStandard = headDay.concat(HEAD_DATE_TIME_SUFFIX);
        LocalDateTime parse1 = LocalDateTime.parse(startTime, YYYY_MM_DD_HH_MM_SS);
        LocalDateTime parse2 = LocalDateTime.parse(headStartTimeStandard, YYYY_MM_DD_HH_MM_SS);
        if (parse1.isAfter(parse2)) {
            head.setStartTime(startTime);
            dayInfoList.set(0, head);
        }
        //获取尾天
        dayInfo last = dayInfoList.get(dayInfoList.size() - 1);
        String lastDay = last.getDay();
        String headEndTimeStandard = lastDay.concat(LAST_DATE_TIME_SUFFIX);
        LocalDateTime parse3 = LocalDateTime.parse(endTime, YYYY_MM_DD_HH_MM_SS);
        LocalDateTime parse4 = LocalDateTime.parse(headEndTimeStandard, YYYY_MM_DD_HH_MM_SS);
        if (parse3.isBefore(parse4)) {
            last.setEndTime(endTime);
            dayInfoList.set(dayInfoList.size() - 1, last);
        }
        //返回结果
        return dayInfoList;
    }

    /**
     * 获取两个日期之间所有的日期（前闭后闭）
     *
     * @param startDate
     * @param endDate
     * @return
     */
    public List<String> getDayList(String startDate, String endDate) {
        List<String> days = new ArrayList<>();
        LocalDate sd = LocalDate.parse(startDate, YYYY_MM_DD);
        LocalDate ed = LocalDate.parse(endDate, YYYY_MM_DD);
        if (sd.isBefore(ed) || sd.isEqual(ed)) {
            days.add(startDate);
            while (ed.isAfter(sd)) {
                sd = sd.plusDays(1);
                days.add(sd.format(YYYY_MM_DD));
            }
        }
        return days;
    }
}

运行效果：

DemoApplicationTests.dayInfo(day=2022-04-10, startTime=2022-04-10 09:00:00, endTime=2022-04-10 23:59:59)
DemoApplicationTests.dayInfo(day=2022-04-11, startTime=2022-04-11 00:00:00, endTime=2022-04-11 23:59:59)
DemoApplicationTests.dayInfo(day=2022-04-12, startTime=2022-04-12 00:00:00, endTime=2022-04-12 18:00:00)